It is so fucking irritating to hear the "blood of a thief, so she's a thief" logic for the...

i mean today people still have that same mindset. either based off of race or a rumor bout someones past theyll just think that way no matter what

It’s a sad stereotype to think people from the past were much different from us, in particular when it comes to social interactions, we share so much with any social animals that recent biology will qualify most of our behaviors and all emotions as the fruit of evolution : which is probably why skystriredtm is absolutely right.

Rumors, gossip and such makes no sense in our megapoles, but must have been very useful if we consider we lived for millennias as very small group where reputation mattered a lot. It must have been powerful regulators of social behaviors.

(When it come to the ridiculous concept of « race »(purely human biais) it probably more akin to in tribe vs out tribe regulation (basically morality is easily suspensed when facing « out tribe », which is why dividing people on any criteria has prove to be absolutely dangerous (lots of social studies in the 60s 70s))

You are also very right, there’s a very heavy emphasis on « blood » and it doesn’t make much sense. Writing any information in DNA is so immensely costly that obviously we’re not born knowing the trades of our family (Even parenting needs to be learned !)
On the contrary though, it seems there are scientific evidence that the trauma of grand parents can be passed down to their grandchildren through epigenetic manifestation (basically because female babies have all the eggs of the ovary very early as embryos). I don’t really recall precisely but these can go down 2 or 3 generations, and leave some issues to be solved that cannot make sense otherwise (family constellation theories ?)

Even if knowledge were of a different kind, it’s only in fantasy that you find total absence of culture (like no cooking knowledge !), but that’s a different story. :)